Melt butter in Dutch Oven over medium high heat and add diced potatoes. Cook for 5 minutes. Add diced onion, celery and bell pepper for 5 more minutes or until veggies get a bit tender and potatoes are beginning to soften. Add the flour a little bit at a time, stirring to thicken the butter into a sort of roux for 1-2 minutes.
Stir in the beef broth a little bit at a time until smooth. Add the Worcestershire sauce and hot sauce and mix. Simmer until the vegetables and potatoes are soft to your liking, around 10-15 minutes.
Add the heavy cream and simmer for about 5 minutes, once done, remove from heat and add in the cheddar cheese. Set your oven to broil and add the sliced cheese to the baguettes and place on a foiled lined baking sheet and broil for about 4-5 minutes or until bubbly.
In a large pan add about 1 tbsp of any oil of your choice and began cooking the thinly sliced steak over a medium high heat until browned. (if using leftover precooked beef you can skip this step or just warm quickly)
Fold the cooked steak into the soup to warm together for a few minutes - or put on the bottom of each bowl with soup poured over the top. Serve with the cheese baguettes and top with parsley (optional) and serve!